1. Field of the Invention
The present invention relates to color processing of a captured image.
2. Description of the Related Art
An image sensing device such as a digital camera internally holds a plurality of profiles for color processing in advance and performs color processing of captured image data by selectively using a profile according to a selected image capturing mode. In other words, a user can set only those profiles (color processing conditions) provided in advance, and therefore user's preferred color representation is sometimes not realized.
In these days, users of digital cameras want to generate an optimal color processing condition in a given image capturing environment.
The present inventor has proposed a method of editing a color processing condition that allows a user to freely set the color representation of a digital camera according to user's preference (see Japanese Patent Laid-Open No. 2004-341923). According to this editing method, a color chart including skin color, the color of the sky, the color of grass, garish colors, and the like is captured by a digital camera in a given image capturing environment. Then, a color processing condition can be obtained that brings the captured image data closer to the original colors of the color chart or to colors (to be referred to as target colors, hereinafter) that are preferable for a user, for example, skin color, the color of the sky, the color of grass, garnish colors, or the like.
It is difficult to appropriately capture a color chart in a given image capturing environment. For example, when capturing a color chart outdoors, the color chart may not be uniformly illuminated because of the influence of a shadow or the like. Also, indoors, an illumination such as a fluorescent light may reflect on the color chart.
In a color chart, the patch image of a shadow portion and a patch image reflecting an illumination are poor in reliability as a patch image for generating a color processing condition. A color processing condition generated from a patch image with poor reliability contains a large error.
A method of editing a color processing condition described in Japanese Patent Laid-Open No. 2004-341923 can automatically change the weight according to whether the color value of each patch of a color chart falls inside or outside the target color gamut (e.g., an sRGB, AdobeRGB, or the like) upon generating a color processing condition. However, this editing method does not consider the reliability of a patch image that depends on the condition upon image capturing. In addition, with this editing method, a user cannot interactively change the weight with respect to a given color patch.